Micro Places – Mazeika (2014)

Study Reference:

Mazeika, D. (2014). General and specific displacement effects of police crackdowns: Criminal events and “local” criminals. (Doctoral dissertation, University of Maryland at College Park, MD)

Location in the Matrix; Methodological Rigor; Outcome:

Micro-places; General; Proactive; Rigorous; Effective

What police practice or strategy was examined?

The study examined the “Summer Crime Initiative” (SCI), a place-focused, arrest-driven police crackdown in Washington, DC aimed at reducing violent crime, gun-related offenses, and drug-related offenses. The SCI took place between May 1 and July 31, 2011, and involved 24-hour police patrols in five crime hot spots of violent and drug offenses identified using reported crime data and street-level intelligence. Officers were placed on rotated 12-hour shifts, 24 hours a day, 7 days a week, in each hot spot. They focused on increasing arrests in the five hot spots during the intervention period. Compared with the three preceding months, arrests went up by 41.4% during the intervention period, which was accounted for primarily by quality of life and low-level traffic violations.

How was the intervention evaluated?

The study examined arrests, offense reports, and calls for service in the intervention hot spots for the treatment period, five months after the treatment period, and one year before the intervention. Trends in the target locations were compared to those in control (non-crackdown) hot spots selected based on similarity to the treatment hot spots using demographic information, crime information, and police presence information.

What were the key findings?

Control areas had an increase in robberies (+2 per month), while the target locations experienced 4.1 fewer robberies per month during the intervention. However, the effect of the SCI decayed during the five-month follow-up period; target locations experienced an average 2.65 increase in robberies per month, and control locations had a decrease of more than 3 robbery calls per month. There was no evidence of crime displacement during the SCI.

What were the implications for law enforcement?

A hot spot crackdown effectively reduced robberies in five crime hot spots during the intervention period. However, the deterrence effects decay less than one year after the intervention ends. A “crackdown” intervention has positive short-term results in reducing crime but may not be effective for longer-term results.

Where can I find more information about this intervention, similar types of intervention, or related studies?